1. Field of the Invention
The present invention relates to an expiration cassette for a ventilator.
2. Description of the Prior Art
One problem encountered with ventilators involves their disassembly for cleaning and subsequent re-assembly. This particularly concerns the ventilators expiration section that can include an expiratory valve, a flow meter, a pressure gauge, filters etc.
A simple, sturdy device, allowing replacement of the expiratory components for cleaning in a simple operation, is therefore needed. Ensuring correct reassembly of the cleaned ventilator parts after cleaning (or of dean parts) is also important in this context.
An object of the present invention is to achieve a device which solves the above need.
The above object is achieved in accordance with the principles of the present invention in a expiration cassette that is removably insertable in a receiving section of a ventilator, the expiration cassette having a gas passage, an expiratory valve and a flow meter, and further having a locking mechanism for locking and unlocking interaction with the receiving section in the ventilator.
Placing the desired components, such as a valve, flow meter, pressure gauge etc. for the ventilator""s expiration section in a cassette reduces the need for disassembly for cleaning. The entire cassette is appropriately devised for cleaning as a single unit. The cassette itself is disassembled only in exceptional instances.
Correct insertion of the cassette into the ventilator is assured with a locking mechanism that interacts with a receiving section in the ventilator.
The locking mechanism in one preferred embodiment has a pushbutton on the top of the cassette. The pushbutton can move between an open position in which the cassette can be removed from the receiving section and a closed position in which the cassette is locked into the receiving section. A spring, or the equivalent, is arranged to act on the pushbutton with a force exerted toward the locking position. The pushbutton interacts with one boss or, preferably, two bosses that are mechanically connected to the pushbutton. In the pushbutton""s locked position, the bosses project beyond the outer edge of the expiration cassette. In the pushbutton""s open position, the bosses are inside the outer edge of the expiration cassette. The bosses interact with openings in the receiving section to lock the cassette in place.